luv2ride

Is there a doctor on the list? I will try to describe it the best I can but when I'm starting to engage the clutch from a stop in first gear. Or when I'm rolling through a stop in second gear when clutch is engaged I get a knock sound that comes from what seems to be in the back right corner of the car. I explained it to my mechanic and he couldn't find the problem. And it now seems to be getting worse. I thought it was a engine mount or a transmission mount but at my last tech inspection they couldn't find anything wrong. Has anyone had this problem? Does anyone know what this could be? Thanks in advance.

Ryan

dhicks

Is it one knock or a knock knock knock.....guys, could it be the dual mass going ???? I had this when my dual mass was going but it was from the rear left that it was most noted.....

luv2ride

David,

thanks for the reply. Its just one knock and its from behind the passenger seat. Only happens when clutch is engaged and under load.

Ryan

dhicks

OK....not the dual mass then.......sorry no further help here....anybody else out there?

deltawedge

A CV joint perhaps (inner or outer).

luv2ride

That sounds a little more like it. Thanks ken. I have to get this taken care of before my next trac day. I hate it when my toys dont work 100%.

911-TOUR

CV Joint.

ZombiePorsche44

+3 on the CV......Good Luck........ZP44

Analog Theory

a right rear PSS9 in need of repair.

Mike J

I don't think its a CV joint since it would be a repeating noise, not just a clunk. if the joint itself were shot it would also clunk on power on as well as power off. Does it do this?

When the suspension is under load there are lots of torsional stresses though the drivetrain and suspension. It could be from a number of sources including all worn bushings, sway bar bushings, shock mounts, etc.

I assume your mechanic has looked it over, tugged on the appropriate parts and declared it all snug and tight?

Does it also clunk under braking (i.e. the load on the rear suspension is the opposite as under acceleration?).

It could be the shocks but there are other spots in the area to look as well.

Cheers,

Mike

luv2ride

I do have pss9's.. hmmm

Mike,

Only when power on.

Yes but it was early on when I couldn't have him hear what I was hearing. Now it's a bit more noticeable and I will be back to the shop to find the culprit.

No clunk during braking.

Hopefully next week I will get a chance to bring it in and solve it. I'll let you know. Thanks

Toga

Luv2ride,

I had a similar "clonk" problem a while ago after an engine drop. It came from a bolt on the gearbox support. The first picture shows you the support from below to help you to locate it. Here you have 6 bolts I would doubt that all six are loose...



but here on the tip of the arrow is the one and only one bolt holding the gearbox to the support. Mine was the source of the noise. It's of course accessible from below the car, but this was the only view I had. I hope this helps

luv2ride

JP,

Outstanding photo's! Thank you. I've been out of town and away from my computer. Hopefully soon I will be able to creep under the car and check. I hope that's it. "clunk" that's right. I'll let you know and if it is in fact those bolts I'll owe you a sweet Belgian beer. Thanks!

Toga

Fingers crossed!

NeufCentOnze

Very interesting! I have observed a similar clonk noise on my C4S a few times. It only happens when I engage the clutch when the car is cold, just leaving the garage.
It does not happen while driving or may be the engine/driving noise hides the clonk noise.
I will check the bolt(s) as indicated by Toga.

Thanks for posting this.
Chris